Sustainable livelihood strategy for shrimp farmers in Mekong Delta under the climate change context. A case study in Tra Vinh province, Vietnam

In Vietnam, the brackish shrimp farming industry has brought a big profit for farmers in recent years. In fact, the brackish shrimp farming industry has been developing since 1980 (EASRD, 2006; MARD, 2015). It was cultivated from the North to the South of Vietnam, especially in the Mekong Delta, where it accounted for 91% (699,725 hectares) shrimp farming land in 2014, with an average growth rate of 3.12% per year from 2010 to 2014 (MARD, 2015). In 2018 shrimp productivity of Mekong Delta approximately accounted for 83% of the total national shrimp production, with an average growth rate of 8.85% per year from 2010 to 2018 (GSO, 2020). In particularly, Tra Vinh province is one of twelve provinces in Mekong Delta, it is suitable for brackish shrimp cultivating with a 65km coastal line and a density system of rivers and canals. According to The Department of Natural Resource and Environment of Tra Vinh province, 110 canals level 1 with a total length of 467 km; 690 canals level 2 with a total length of 2,110 km; 8,800 canals level 3 with a length of 6,620 km. And it also has been projected by Tra Vinh authority considering the shrimp industry as a vital economic strategy. By 2019 Tra Vinh province’s shrimp farming land expanded to 33,378 hectares and achieved 67,768 tons shrimp production with an average growth rate of 21.5% per year from 2010 to 2019 (Aquaculture Department of Tra Vinh). In addition, Decision 784/QD-UBND of Tra Vinh province dated 27 April 2018 ‘Developing shrimp farming industry to 2025’, it has planned to develop shrimp production basing on each natural condition area. Whereas the intensive and semi-intensive methods should continually develop and apply new technology in farming without abusing chemicals and antibiotics, forward to acquire a certificate of eco-environment meeting the exporting markets’ requirement. And the extensive shrimp farming should consolidate and maintain to preserve the existing mangrove forest and to balance the ecosystem. However, the shrimp industry is facing with the environmental problem seriously. According to MARD (2015), the degree of pollution in rivers was over 2.5 to 3 times the permitted standard. Because a high profit comes from the shrimp industry, the farmers have short sight in environmental responsibility. They were not paying attention to the consequence of abusing some uncontrolled or prohibit chemicals and drug in shrimp farming, in spite of the available regulations of environmental protection law. In addition, small-scale farms are popular in Tra Vinh province, they utilize almost land for shrimp ponds, but they do not have reservation ponds. Hence, wastewater gets directed to rivers or canals, which leads to polluted water resources. And a vicious cycle occurs when farmers use that polluted water for new crops: it is a big risk for disease outbreaks. Furthermore, under the climate change context, the shrimp farming industry has suffered significant damage and loss in recent years. According to the Aquaculture Department of Tra Vinh province, in 2019, there were 6,238 shrimp farming households damaged with 2,121ha of shrimp farming damaged due to drought, fluctuation of temperature and epidemic disease, accounted for 19% of total shrimp farming area excluding extensive production (Aquaculture Department of Tra Vinh). From 1970 to 2007, the average temperature increased by 0.6 Celsius, and average precipitation rose more 94mm per year (MARD, 2015). By 2100, under the A2 scenario of 1-meter sea-level rise (SLR) will sink 85% of the Mekong Delta area (12,376 sq. km). Tra Vinh province, particularly, will lose up to 45.7% of the area of natural land and coastal land for aquaculture farming be disappeared totally (Carew-Reid, Jeremy, 2007). Accompanying with SLR, average temperature also was estimated about 30C increasing which will affect almost all economic areas but shrimp farming in particular by 2100 (MORE, 2008). According to scenario A2 of IPCC, the rainfall in this area will increase about 3% and 7% by 2050 and by 2100 respectively, so Tra Vinh province is predicted to suffer more rainfall in the future, especially focusing on coastal areas where is considered as the most suitable for shrimp farming (JICA, 2013). In addition, to be in the predicament with adverse climate patterns and pollution problems, which cause farmers using more chemicals and drugs in shrimp farming inevitably. Overusing drugs and chemicals problem is not only harmful to the environment around, natural ecosystem but also affects customers’ health due to the residual substances in shrimp products. This lost the prestige and image of Vietnam’s aquatic products on the international markets. According to MARD, in recent years shrimp export products have been rejected by many importers related to food security, residual antibiotics. Therefore, Vietnam’s shrimp is finding it difficult to penetrate new foreign markets and being observed strictly by the traditional markets. For instance, at the current time, 100% of shrimp shipments from Vietnam must be inspected by Japan’s custom, instead of testing 30% of the volume as usual; and Korea has also dispatched a warning that the presence of residual Nitrofurans in Vietnam’s shrimp products (VASEP, 2020). Hence, in 2011 the Ministry of Agricultural and Rural Development (MARD) promulgated the Vietnam Good Aquaculture Practice (VietGAP) standard to address the aquatic industry develop sustainably. The VietGAP is the guideline of aquaculture practice comprising five fundamental criteria, acronyms of ‘five S’, that are safe food; safe health of shrimp; a safe environment; social responsibility, and showed traceability information. The core of VietGAP is the list of criteria relating to ecological and environmental requirements adopted by the process of shrimp farming. With the purpose of maximizing the regulatory functions of nature by composing environmental conditions favorable for the sustainable development of shrimp farming with less compromising natural resources as much as possible. At present, the Government is deeply concerning and encouraging the farmers for applying VietGAP standard in shrimp farming. The MARD expected that VietGAP would be applied by 80 percent of shrimp farmers by 2020. However, the current number of certified farms is insignificant with only 128 shrimp farms in total (vietgap.tongcucthuysan.gov.vn). In particular, there is only one shrimp farmer getting a VietGAP certificate in Tra Vinh province. Overall, shrimp farming is the main livelihood for more than 44.000 householders in Tra Vinh province by 2019 (Aquaculture Department of Tra Vinh). Climate change has posed an adverse risk for their livelihood, as well as the pollution water resource due to the shrimp farmers’ behavior is more and more threatening to the shrimp industry. The thesis aimed to assess the current status of shrimp farmers’ livelihood assets which affect the environmental sustainability in shrimp farming, and analyze the livelihood vulnerability index (LVI) to climate change. Another purpose of the thesis was to find out whether the farmers’ responsibility to the environment by estimating the willingness to accept (WTA) an incentive program for pursuing the eco-environmental certificate (VietGAP). In the following, I summarize each of three papers and highlight their contributions to the literature. In chapter 2, the data collected from 300 shrimp households in 2019 in Tra Vinh province through questionnaire interviews and transect walks. The study based on the DFID’s Sustainable Livelihood Framework which has 5 types: Human capital; Natural capital; Physical capital; Social capital, and Financial capital to analyze the current status of shrimp farmers’ livelihood assets. And to estimate the effects of five livelihood capitals and 17 indicators of them to the environmental sustainability of shrimp farming which is measured by the 19 criteria. The study revealed that the current livelihood assets and level environmental sustainability of extensive, intensive, and semi-intensive farming systems was ranked increasing in order. And three livelihood assets that were human, natural, and financial capitals had a positive relationship with the environmental sustainability in shrimp farming. In particular, using groundwater in shrimp farming was not sustainable for shrimp farming in term of environmental sustainability, while having reservation pond had positive impact on environment sustainably. In chapter 3, the study measures the Livelihood Vulnerability Index (LVI) of shrimp farmers to climate change by comparing three shrimp farming systems in Tra Vinh province, Vietnam. The analysis is based on the IPCC’s framework of vulnerability assessment through three contributing dimensions (exposure, sensitivity, and adaptive capacity). A total of 42 indicators were proposed for those dimensions conforming to livelihood capitals (human, physical, natural, social, and financial capital) under the Sustainable Livelihood Framework (SLF) of Chambers and Conway (1992). A total of 300 surveyed households comprising 195 samples, 62 samples, and 43 samples for intensive, semi-intensive, and extensive production respectively. In general, the results indicated that shrimp farmers were vulnerable at a medium level. The extensive farming was the highest vulnerability to climate change among the three methods of shrimp farming. In particular, intensive farming was highly vulnerable to climate change in term of natural capital, social capital and financial capital while extensive farming was the most vulnerable with the human and physical capital. Although intensive shrimp farming is usually invested more properly in facilities and equipment, with a high density of stock farming caused it was more vulnerable to climate change than the semi-intensive. Chapter 4 uses the contingent valuation method to find out what factors affect the farmers’ decision on following the VietGAP certification (WTADecision) and how much subsidy value they are willing to accept (WTASubsidy) to pursue the VietGAP standard. The results showed that WTADecision had a positive relationship with farmers’ education level, environmental perception, and attitude toward the VietGAP certificate. While those factors had negative effects on WTASubsidy. Besides, the annual income also had a slight effect on farmers’ willingness to accept a subsidy value. The study’s findings suggest that the authority should increase the subsidy at the first phase scheme, and improve the farmers’ environmental perception, propagandize benefits of VietGAP certificate to attract the farmers to participate in. This research makes contributions to the sustainable livelihood strategy of shrimp farmers under the climate change context. - Building the criteria for environmental sustainability of shrimp farming - Finding out the relationship between livelihood assets and the environmental sustainability of shrimp farming. - Composing the indicators for three dimensions of vulnerability assessment to climate change based on the five livelihood assets. - Finding out the difference of livelihood vulnerability to climate change between three shrimp farming systems. - Find out factors affecting the Willingness to accept a subsidy for pursuing the VietGAP certification

Tribological behaviour of polymer bearings under dry and water lubrication

This study attempts to evaluate the performance of polymer journal bearings (PET and UHMWPE) sliding against Inconel stainless steel in both dry and lubricated condition. Four types of ‘lubricant’ are included: distilled water; demineralized water; tap water and river water. The tests were carried out in a so called “Stribeck” configuration with a projected pressure of about 0.3 MPa at room temperature and sliding speed ranging from 0 to 1.07 m/s respectively. The study indicates that polymer bearings with four types of water lubricant give better tribological behaviour compared to those in dry sliding contact. Besides, with water lubrication, UHMWPE shows low friction at starting, but it does not go down much over the course of the tests. Meanwhile, although PET indicates quite higher friction at the beginning, it then shows a clearly decreasing trend

RECOGNIZING LINGUISTIC NON-MANUAL SIGNS IN SIGN LANGUAGE

Ph.DDOCTOR OF PHILOSOPH

Chapter 9 Discussion and Conclusions

This chapter presents a reflection on the main findings of the research performed for this thesis, and the conclusions drawn from the results. The research was guided by the following main research question: How can the complex field of mental health problems among adolescents in Vietnam be understood and addressed with sustainable and accessible developments at the secondary school level

Chapter 3 Research Methods

The main research question for this thesis is: How can the complex field of mental health problems among adolescents in Vietnam be understood and addressed with sustainable and accessible developments at the school-level

Mobile charging and data gathering in multiple sink wireless sensor networks: how and why

Recently, the problem of using efficient the number of mobile devices starting from multi-sink to go to charge and collect data of sensors such that sensors can work forever has received a great deal of attention in Wireless Rechargeable Sensor Network (WRSN). Many methods have been proposed for the WRSN systems such that mobile device can charge and collect data from sensors. However, most of previous works often require lots of mobile devices while the cost of mobile device is very high. In this paper, we investigate the Periodic Energy Replenishment and Data Collection with multiple sink (PERDCMS) problem and propose a new algorithm, called the Mobile Device Scheduling Algorithm (MDSA), to using limited number of mobile devices for charging and collecting data for sensors. Simulation results show that the MDSA has better performance than other method

Orange Peel Essential Oil Nanoemulsions Supported by Nanosilver for Antibacterial Application

This study is devoted to the synthesis of King Orange peel essential oil in water nanoemulsions combined with nanosilver by ultrasonic method supported by mechanical stirring for antibacterial application. The samples were characterized by Gas chromatography-mass spectrometry (GC-MS), Ultraviolet–visible (UV-Vis), Transmission electron microscopy (TEM), and Dynamic light scattering (DLS) methods. According to the above-experimental results, it was found that the emulsions based on orange essential oil (without nanosilver) and the ones combined with nanosilver have the average particle size from 66.2 nm and 42.9 nm, respectively. The obtained nanoemulsions were also tested to examine their antibacterial ability against Escherichia coli (E. coli) by the disc diffusion method. It has been also found that nanoemulsions based on orange essential oil supported by nanosilver have the superior antibacterial ability, compared with individual components of the materials

Radiotherapy for marginally resected, unresectable or recurrent giant cell tumor of the bone: a rare cancer network study

The role of radiotherapy for local control of marginally resected, unresectable, and recurrent giant cell tumors of bone (GCToB) has not been well defined. The number of patients affected by this rare disease is low. We present a series of 58 patients with biopsy proven GCToB who were treated with radiation therapy. A retrospective review of the role of radiotherapy in the treatment of GCToB was conducted in participating institutions of the Rare Cancer Network. Eligibility criteria consisted of the use of radiotherapy for marginally resected, unresectable, and recurrent GCToB. Fifty-eight patients with biopsy proven GCToB were analyzed from 9 participating North American and European institutions. Forty-five patients had a primary tumor and 13 patients had a recurrent tumor. Median radiation dose was 50 Gy in a median of 25 fractions. Indication for radiation therapy was marginal resection in 33 patients, unresectable tumor in 13 patients, recurrence in 9 patients and palliation in 2 patients. Median tumor size was 7.0 cm. A significant proportion of the tumors involved critical structures. Median follow-up was 8.0 years. Five year local control was 85% . Of the 7 local failures, 3 were treated successfully with salvage surgery. All patients who received palliation achieved symptom relief. Five year overall survival was 94%. None of the patients experienced grade 3 or higher acute toxicity. This study reports a large published experience in the treatment of GCToB with radiotherapy. Radiotherapy can provide excellent local control for incompletely resected, unresectable or recurrent GCToB with acceptable morbidity

Relationship between self-esteem and suicidal ideation before and during COVID-19 in a non-clinical sample: mediating effects of psychological distress and hopelessness

IntroductionSeveral studies have highlighted the impact of the novel coronavirus disease (COVID-19) pandemic on suicide. Accordingly, investigating the risk factors of suicide during this crisis is important. Based on the escape theory of suicide, the current study examined the serial mediating roles of psychological distress and hopelessness in the relationship between self-esteem and suicidal ideation. It also aimed to explore whether or not the COVID-19 pandemic changed the mediation effect in any way.MethodsData were collected from 645 university students before and during the pandemic. The study employed mediation and multi-group analyses to test the hypotheses.ResultsThe results demonstrated that individuals with low self-esteem reported high psychological distress, which further lead to hopelessness and eventually heightened suicidal ideation. Multi-group analysis revealed that psychological distress exerted a greater impact on suicidal ideation during COVID-19.DiscussionThe finding suggested that self-esteem, hopelessness, and psychological distress could help elucidate the development of suicidal ideation. Clinicians may target these factors in suicide prevention programs, particularly in the settings of the COVID-19 pandemic or future crisis